Nonaqueous dye bath



Patented Apr. 15, 1930 UNITED STATES PATENT OFFICE It. SGHLAT'IEER, F LITTLE FALLS, NEW JERSEY, ASSIGNOR TO DIP-1'1 INC.,

v NEW YORK, N. Y., A. CORPORATION OF NEW YORK noNAQuEoUs DYE BATH No Drawing.

This invention relates to certain improvements in the art of dyeing fabrics and more particularly to the preparation. of solutions of coal-tar dyes in non-aqueous solvents for 5 thepurpose of dyeing fabrics for which aqueous dye-baths are not wellsuited.

Nearly all commonly used fabrics will lose their shape and shrink when immersed in water, and generally a subsequent ironing 1 treatment of some sort has to be given the fabric to restore the original smooth appearance. This feature is especially troublesome with lace work and other delicate fabrics, particularly when already made up into a finished article or garment. Other solvents, like the various alcohols, acetone, benzol, gasoline, etc., have no such detrimental effect on the fabrics, and the practical dyerwould often resort to the use of such non-aqueous dye-baths were it not for the fact that many of the coal-tar dyes which he usually employs are either insoluble in such organic solvents or only so little soluble that the dyeing efi'ect produced is not entirely adequate.

Now, I.have found that glycerin has the .property of dissolving most of the acid, basic and substantive coal-tar dyes and various mixtures thereof to an extent hitherto not realized nor applied in this art. This hither- 33 to unknown property of glycerin in relation to coal-tar dyes has been set forth in detail in my 'co-pending application, Serial No.

28,731 (1925). filed June 7th, 1925.

In working with such glycerin dye-solu tions I have found that it is possible to mix them with, for instance, methyl, ethyl, propyl, butyl andamyl alcohols, and with acetone and other organic solvents which dissolve glycerin and thereby produce dye-baths for the successful dyeing and tinting of fabrics 'without streaking, spotting or shrinking,"

even when the dyestuffs are by themselves insoluble in these organic solvents. This was an unexpected result, as the quan .tity of glycerin which enters into the dyebath is by itselfinadequate to change the predominant physical properties of the other solvent. It is not possible. for instance, to add to similar amounts of these alcohols the same quantity of glycerin as would be added Application filed March 13, 1926. Serial No. 94,590.

to them in .the form of the glycerin solution of the dye-stuff required to produce the result above described, and then to dissolve the dyestuffs in the mixture. To illustrate this point furtherI give the following example:

Diamine Fast Yellow (Schultz 1914 Nr. 617) is not sufliciently soluble in alcohol to produce solutions that would dye any fabric to a satisfactory shade. However, I can produce solutions in glycerin, for instance, dissolving 1 gram Diamine Fast Yellow in 200 cc. glycerin. Upon adding a few drops of this glycerin solution to 250 cc. of alcohol I obtain a deeply colored alcoholic dye-bath that will dye silk, wool or cotton yellow, the depth of the shade depending on the quantity of the glycerin solution used.

' On the other hand, if I were to add the same number of drops of glycerin to the same amount of alcohol as indicated above and then add the same relative quantity of Diamine Fast Yellow as is contained in the quantity of the glycerin-dye solution before employed, practically no solution of the dyestufi' takes place beyond the quantity which will dissolve in the alcohol alone. 1 believe that the explanation for this difference in results observed is that the dyestulf, when mixed as a glycerin solution with the alcohol, is in such fine dispersion in the solvent that itremains in colloidal solution a suflicient length of time to permit the practical application of such solutions for the dyeing of fabrics. This explanatlon 1s also borne out by the fact that the dyestuff Wlll settle outfrom such a alcohol-glycerin solution on standing and finally a solution results which is as little colored as a saturated solution of Diamine Fast Yellow in alcohol would be, while the precipitated dye can be noticed at the bottom of the vessel.

For further illustration I give the following example: I have found that a glycerin solution containing 0.1% Methyl Violet Schultz No. 515) and 0.9% Methylene Blue ESchultz No. 659) gives, when added to water, a dye-bath with uniform dyeing efiect on silk, wool and cotton. Now one of these two dyes, Methyl Violet, is quite soluble in alcohol, whereas Methylene Blue is only sparingly soluble in this solvent. Therefore, when these two'dyes, substantially in the proportion 1:9 as indicated above, are

added to alcohol, practically only the one dye,

the-Methyl Violet, goes into solution, and,

after filtering from the undissolved Methylene Blue, a dye-bath is obtained which is not suitable for dyeing silk, wool' and cotton promiscuously. If, however, a few drops of the above-mentioned glycerin solution of these two dyes are added to alcohol, the entire amount of dyestuiis,'sd predissolved in the glycerin, goes into solution and the dye-bath thus obtained can be used for the dyeing of silk, wool, cotton and mixtures thereof.

1 am familiar with the work of Albert David and his inventions covered by several co-pending applications, especially Serial No. 546,799, filed March 25th, 1922, relating tothe use of glycerin presolutions of coal-tar dyes for preparing extemporaneous aqueous dye-baths, and this invention is an improvement and further development of the work done by that inventor along these lines.

The examples set forth herein are given for the purpose of illustration only, and I do v not intend to limit myself to the specific embodiments therein set forth, since the invention described is obviously of a range which will permit its use in a wide field of application as to the employment of many difierent individual dyes of similarly diverse physical and chemical properties, as to relative solubility in glycerin and other menstrua, and is also susceptible of considerable variation as ly soluble in glycerin, and glycerin; the said dye being present in excess of the amount which can be dissolved 'in the same quantity of a mixture of alcohol and glycerin in the proportions in which they are contained in the dye bath.

2. An alcoholic dye-bath comprising alcohol, a coal-tar dye scantily soluble in alcohol but freely soluble in glycerin, and glycerin; the said dye being present in excess of the amount which can be dissolved in the same quantity of a mixture of alcohol and glycerin n the proportions in which they are contained in the dye bath. i

3. A non-aqueous dye-bath consisting of a solvent which will dissolve glycerin, a coaltar dye scantily soluble in said solvent but freely soluble in glycerin, and glycerin; the said dye being present in excess of the amount which can be dissolved inthe same quantity of a mixing of alcohol and glycerin which could in the proportions in which they are con tained in the dye bath.

4. A dye-bath which consists of a nonaqueous menstruum which is a solvent of glycerin and a dye not freely soluble in the said menstruum, but which is freely soluble in glycerin, and glycerin; the said dye 'bein present in excess of the amount which can be dissolved in the same quantity of a mixture of alcohol and glycerin in the proportions in which they are contained in the dye bath.

.5. An alcoholic dye-bath comprising a glycerin solution of Diamine Fast Yellow (Schultz, 1914 #617) and alcohol, wherein the dye is partly in solution and partly dispersed in alcohol.

. 6. An alcoholic dye-bath'having dispersed v therein a glycerin solution of a coal-tar dye, which is freely soluble in glycerin but scantily soluble in alcohol, the said dye being pres ent in such dye bath in a quantity in excess of that which the alcohol alone would dissolve. .7..An alcoholic dye-bath having dispersed therein a glycerin solution of Diamine Fast Yellow (Schultz, 1914., No. 617) in'a quantity in excess of that which the alcohol will dissolve. I

8. A dye-bath consisting of a mixture of dye which is less soluble in alcohol than it is in glycerin, the said dye being'present in a quantity in excess of that which would go. into truesolution in the alcohol alone or which would dissolve in a. mixture of alcohol and glycerin of the same proportions'in which they are contained in the dye-bath.

9. A dye-bath consisting of 'a mixture of alcohol and a glycerin-solution of a coal-tar dye which is less soluble in alcohol than it.is in glycerin, the total quantity of'the said dye being present being in excess of the quantity be taken up by the said alcohol alone.

10. The process of preparing alcoholic dyebaths which consists of dissolving in said bath Diamine Fast Yellow (Schultz, 1914, No. 617) predissolved in glycerin, the amount of the dye being in excess of the quantity whiah will dissolve in the quantity of alcohol use 11. A non-aqueous dye-bath having dispersed therein a solution of coal-tar dye in into true solution in the said menstruum alone or in a mixture of the same relative quantities of said menstruum and glycerin as are contained in the completed dye bath.

EUGENE R, SCI-ILATTEB. 

